Water Caltrop (Trapa quadrispinosa Roxb.) Husk Improves Oxidative Stress and Postprandial Blood Glucose in Diabetes: Phenolic Profiles, Antioxidant Activities and α-Glycosidase Inhibition of Different Fractions with In Vitro and In Silico Analyses

Abstract

The aim of this study was to investigate the phenolic profiles, antioxidant activities and α-glycosidase inhibitory activities of three different phenolic fractions from water caltrop (Trapa quadrispinosa Roxb.) husk and to further explore the predominant compounds and their mechanisms on α-glycosidase inhibition by virtual screening and molecular dynamics. A total of 29 substances were identified and quantified in this study. Tannins were the main constituents of water caltrop husk extract. All of the free phenolic (FP), esterified phenolic (EP) and insoluble-bound phenolic (BP) fractions exhibited good antioxidant activities, and the BP had the highest radical scavenging ability with IC50 values of 0.82 ± 0.12 μg/mL (ABTS) and 1.15 ± 0.02 μg/mL (DPPH), respectively (p < 0.05). However, compared with the EP and BP, the FP showed the strongest inhibition towards the α-glycosidase and the IC50 value of FP was 1.43 ± 0.12 μg/mL. The 1,2,6-trigalloylglucose and α-glycosidase complex had better root mean square deviations (RMSD) stability via molecular dynamics simulation study. Results obtained from this study may provide a good potential natural resource for the improvement of oxidative stress injury and blood glucose control in diabetes mellitus, which could expand the use of water caltrop husk and improve its economic value.

Exploring antioxidant activities and inhibitory effects against α‐amylase and α‐glucosidase of Elaeocarpus braceanus fruits: insights into mechanisms by molecular docking and molecular dynamics

“…The outcomes showed a significant positive correlation between the free radical scavenging ability (ABTS and DPPH) of E. braceanus fruits and both its TPC and TFC (r = 0.97 and 0.97, P < 0.01). This suggests that the phenolics and flavonoids present in E. braceanus fruits are highly responsive to ABTS and DPPH radical scavenging, which was similar to the findings of Zhang et al (2022).…”

“…In this study, 100-ns MD simulations were used to further investigate the stability of complexes formed by quercitrin and myricitrin with α-amylase and α-glycosidase. The MD simulation was performed through the root mean square deviations (RMSD), the root mean square The RMSD indicates the stability of protein-ligands and conformational changes of the ligand in binding sites during the course of MD simulation (Ponneganti et al, 2022;Zhang et al, 2022). Figure 6a1 and b1 show the RMSD results for protein ligands of quercitrin and myricitrin with α-amylase and α-glycosidase, respectively.…”

“…The methodology suggested by Zhang et al (2022) and Shadakshari et al (2023) was employed for conducting molecular docking and MD simulations. In brief, molecular docking was performed using the Autodock Vina software (https://vina.scripps.edu/), while MD simulations were conducted using GROMACS 19.5 Package (https://manual.gromacs.org/) based on the outcomes of the former.…”

“…Chronic or persistent diabetes can have multiple negative effects on the body, such as diabetic nephropathy, retinopathy, and neuropathy (Tomic et al ., 2022; Beydag‐Tasoez et al ., 2023). In addition, chronic or persistent diabetes can also induce severe oxidative stress damages to blood vessels, ultimately leading to other diabetic complications, such as retinopathy, nephropathy, and nephropathy (Zhang et al ., 2022; Purwaningsih et al ., 2023). Although certain clinical drugs can alleviate oxidative these stress damages during diabetes treatment (Tamasawa et al ., 2015; Koniari et al ., 2022), these drugs also cause some side effects, such as diarrhoea, anorexia, and nausea.…”

Exploring the Promotive Effects and Mechanisms of Different Polyphenolic Extracts from Prinsepia utilis Royle Seed Shell on Tyrosinase

“…Then, the powder was stored at −20 °C for subsequent experiments. The extraction steps of the free polyphenols (TF), the esterified polyphenols (TE) and the insoluble bound polyphenols (TI) were referred to the method of Zhang et al [ 25 ].…”